Door lock for elevators



* Sept. 25', 1923. 4 3,468,677

J. TT scHLEslNGE'R DOOR LOCK FOR ELEVATORS Filed April 19. 1921 314i) autor,

Patented Sept. 25, 1923i..

renten ate res'earetr JOSEPH T. SCHLESINGEE, OF ESR-K, 1. Y., ASSIGNOR, BY I'JESNE ASSEGNMENTS,

TO UTILITY SAFETY APPLINCE CORPORATQN.

:000B LOCK FOR ELEVATOBS.

Application filed April 19,

To all 197mm. tmag/ conce/m.'

Be it known that I, Josnrir TjSciiLns- Irenn, a citizen ot Hungary, and resident ot the city ot ,New York, in the county or New Yori; and State ot New York, have invented certain new Vand useful Improvements in Door Locks for Elevators, ot which the following is a specication.

The present invention relates to improvements in door-locks for elevators. and more particularly to a door-lock which controls, by theposition of the door, the elevator motor mechanism. Y In some devices ot this type, the doorloclr includes a casing, in which spaced apart contact .plates are provided, the grap between said contact plates beinf bridged over by a metallic member, which is actuated by a slide bar on the door.- These mechanisms have been found objectionable for the reason that an electric arc is apt to be formed between said contact plates when the metallic member is withdrawn Ytherefrom. with the result'that the motor may be started with the door'in open position.

@ne ot Vthe objects of the present invention is to overcome this defect by placing between the Contact plates an arc extinguisher, which is directly controlledby the locking` bar of the device. Y

Another object of the invention is to so devise the extinguisher-that it serves at the same time as a` means tor indicating` the .tact when the elevator door is in its unlocked position.

With these and other objects in view, which will more fully appear as the nature et the invention is better understood, the same'consists in the combination, arrangement and construction ot parts hereinafter described. pointed out inthe appended claim and illustrated in the accompanying drawings, it being; understood that many changes may be made in the Vsize and proportion of the several parts and details of construction within the scope ot the appended claim. without departingitrorn the spirit or sacrificingy any ot the advantages ot the invention.

One of the many possible embodiments of the invention is illustrated in the accompanying drawings, in which:-

Figure 1 is a front elevation, partly in section, ot a door-loch constructed in accordance with the Vpresent invention, the

1921. Serial No. 452,676.

front cover of the lock casing being removed to show the interior construction; Fig. 2 is a side elevation thereoii; Fig. 3 is an elevation similar to the one shown in Fig. 1 ot the drawings of the .lock casing, with the elements in other positions; and Fig'. 4 is a section talren on line 4 4 ot 1.

ln the drawings, the numeral 10 indicates a casing' ot any suitablecenstruction, adapted to be fastened to the door trame of an elevator, tor instance, by screws passing through lugs 11 thereon. rThis casing is provided with a detachable Yiront plate 12. ln the bottom 13 ot the casing is formed an opening 1/1, through which a locking bolt, carried by the elevator door, may be projected into the casing'. The bottom 13 includes two slanting portions 15, which converge toward the opening; 1t. for purpose hereinafter to be described. llir'oni the back plate 16 ot the casing' extends outwards a projection 1'?.y having' an inclined tace 18, slanting toward the said opening'. rllhe purpose ot this arrangement will appear hereinafter.

lNithin the casing; are mounted two iusulating,` blocks 19, one oneach side ot the opening' 14, and to these blocks are tastened. for instance by screws 20, metallic contact plates 21, termina' part ot a switch.

YThe contact plates are, preteraby, made in the form of blade springs, extending' substantially vertically, their lower ends being tree and in operative relation to the opening 111 in the casing bottom. The contact plates are inserted into the motor control circuit ot the elevator, conductors leading to the screws 20, in contact with the plates 21.

l @n the elevator door is mounted a vertically eXtending locking; slide bar 22, movable in guides 28, of which only one is shown in the drawings, said guides being` securely fastened to the door.` The upward movement of the slide bar is limited by a washer 24% thereon, said washer abutting'against the underiace ot one oit the said guides. The slide bar is, preferably, tubular and carries at its upper end a head 25, on which is mounted an insulating bloclr 26, carrying a metallic plug 27. that is adapted to be inserted between the contact plates 21. The plug, is provided with an anti-friction ball 28. adapted to co-operate with the slanting portions 15 or the inclined tace 18 ot the ttl) lUU

projection 17, as the case may be. The head lits the opening 14E in the casing bottom'.

On the front face 0f the insulating blocks 19 is slidably arranged an insulatingr body 29,' in the form Vof a plate member, that is provided on its rear lface with a rib 30, fitting into the gap between the metallic plates 2l. On the front tace of the insulating body may be printed or otherwise provided the word Open, which appears through an aperture 31 in the front plate 12 of the lock-casing when the head 0i' the slidebar is ywithdrawn from the lock-casing. "Whcn this head is inserted into the lock-casing, the insulating body 29 rests upon the anti-friction ball 2S, the latter holding the said body in its elevated position, whereby the word Open is out of registering `position with the aperture 31.

The operation of the device is as follows: Nhen the elevator door is in its closed posif tion, the slide bar 22 projects into the lockcasing, its plug 27 bridging the gap between the cont-act plates 21 and thereby completing the motor control circuit. The lockingbar,

being projected into the casing, holds the door in locked position. Assuming that the elevator door is of the sliding type and moves in the directionof the arrow marked Xin Fig 1 of the drawings to opening position, itis obvious that, in order to open the door, first the slide bar must beshifted downwards in the direction of its longitudinal axisuntil it is completely disengaged from the casing 10, after which t-he door may be moved in the direction ot the arrow mentioned. When the'bar is thus re-A tracted from the casing, the motor control circuit is opened and the elevator cannot be Y started until` the door `is again closed and securely locked. When the slide bai` is soV withdrawn, the inslll.lllllgV bOdy 29` drops by gravity onto the casing bottom, thereby extinguishing any possible electric are that may be formed between the contact plates 21. In shifting the Ydoor toward closing po- 31 in the casing. `Iii the door is movable in a direction opposite to the arrow X, the opposite slantingportion of the casing 15 will act as a striker, and, thedoor is or" the swinging type, the projection 17 will perform this function;

`What claimszfj Y Y ln a door-loch for elevators, the combination with a casing having an opening in its bottom mounted upon the Vdoor frame, of a Y Vlocking slide bar on the elevator door,

spaced apart contact plates within said casing in the motorcontrol circuit of the elevator, a metallic plugcarried by said slidebar for bridging the gapV between saidA contact plates when said bar is projected through said opening into said casing, and an insulating body having a portionlitting the gapk between said Vcontact plates, saidbody being freely slidable in said casing and resting on said plugwhen the latter is within said casing, dropping by gravity onto the casing bottom when said slide bar is withdrawnfrom said casing. A Y Y Signed at New York, fin the county of New York and State of New Yorl, this 9th day of February, A. DQ1921. Y

JOSEPH fr.. SGHLESINGER, Y

soV 

